Catheters are commonly used for a variety of infusion therapies. For example, catheters are used for infusing fluids, such as normal saline solution, various medicaments, and total parenteral nutrition into a patient; withdrawing blood from a patient; or monitoring various parameters of the patient's vascular system. Catheters are typically coupled to a catheter adapter that supports catheter and provides for an attachment to IV tubing. Generally, following placement of the catheter into the vasculature of a patient, the catheter adapter may be coupled to a fluid source via a section of IV tubing to infuse fluids into the patient.
In order to verify proper placement of the catheter in the blood vessel, the clinician generally confirms that there is “flashback” of blood from the patient's vasculature into a flashback chamber of the catheter or catheter adapter. Once proper placement of the catheter is confirmed, the clinician must attach the catheter adapter to a section of IV tubing, or continue to manually occlude the vein to prevent undesirable exposure to blood. The process of coupling the catheter adapter to the section of IV tubing requires the clinician to awkwardly maintain pressure on the vein of the patient while simultaneously coupling the catheter adapter and the IV tubing.
A common, yet undesirable practice is to permit blood to temporarily and freely flow from the catheter adapter while the clinician locates and couples the IV tubing to the catheter adapter. Another common practice is to attach the catheter adapter to the IV tubing prior to placing the catheter into the vein of the patient. While this method may prevent undesirable exposure to blood, positive pressure from the IV tubing into the catheter does not permit desirable flashback and thus reduces a clinician's ability to confirm proper catheter placement.
Some catheter systems utilize a valve or septum disposed within the catheter adapter, as a barrier to control fluid flow through the catheter. Generally, a seal is provided between the septum and an inner surface of the catheter adapter thereby preventing flow of fluids around the septum. In some systems, a slit or perforation is provided in the septum whereby a controlled amount of fluid is permitted to bypass the septum. In other systems, a system of channels is provided between the outer surface of the septum and the inner surface of the catheter adapter, thereby providing a fluid pathway around the exterior of the septum. However, the methods whereby the septum of these systems is sealed within the catheter adapter are prone to undesirable leakage based upon the various compressive forces which are exerted upon a septum during catheterization and subsequent infusion procedures.
Accordingly, there is a need in the art for a catheter assembly that permits controlled, desirable flashback without undesirable leakage. Such a catheter assembly is disclosed herein.